class_docstr: Namespace for expressions that operate on expression names.
docstr: Make the root column name lowercase.
  
  Notes
  -----
  Due to implementation constraints, this method can only be called as the last
  expression in a chain.
  
  See Also
  --------
  prefix
  suffix
  to_uppercase
  
  Examples
  --------
  >>> df = pl.DataFrame(
  ...     {
  ...         "ColX": [1, 2, 3],
  ...         "ColY": ["x", "y", "z"],
  ...     }
  ... )
  >>> df.with_columns(pl.all().name.to_lowercase())
  shape: (3, 4)
  ┌──────┬──────┬──────┬──────┐
  │ ColX ┆ ColY ┆ colx ┆ coly │
  │ ---  ┆ ---  ┆ ---  ┆ ---  │
  │ i64  ┆ str  ┆ i64  ┆ str  │
  ╞══════╪══════╪══════╪══════╡
  │ 1    ┆ x    ┆ 1    ┆ x    │
  │ 2    ┆ y    ┆ 2    ┆ y    │
  │ 3    ┆ z    ┆ 3    ┆ z    │
  └──────┴──────┴──────┴──────┘
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code: def to_lowercase(self) -> Expr:
      """
      Make the root column name lowercase.
  
      Notes
      -----
      Due to implementation constraints, this method can only be called as the last
      expression in a chain.
  
      See Also
      --------
      prefix
      suffix
      to_uppercase
  
      Examples
      --------
      >>> df = pl.DataFrame(
      ...     {
      ...         "ColX": [1, 2, 3],
      ...         "ColY": ["x", "y", "z"],
      ...     }
      ... )
      >>> df.with_columns(pl.all().name.to_lowercase())
      shape: (3, 4)
      ┌──────┬──────┬──────┬──────┐
      │ ColX ┆ ColY ┆ colx ┆ coly │
      │ ---  ┆ ---  ┆ ---  ┆ ---  │
      │ i64  ┆ str  ┆ i64  ┆ str  │
      ╞══════╪══════╪══════╪══════╡
      │ 1    ┆ x    ┆ 1    ┆ x    │
      │ 2    ┆ y    ┆ 2    ┆ y    │
      │ 3    ┆ z    ┆ 3    ┆ z    │
      └──────┴──────┴──────┴──────┘
  
      """
      return self._from_pyexpr(self._pyexpr.name_to_lowercase())
  
file_path: polars/py-polars/polars/expr/name.py
imports: from __future__ import annotations
  from typing import TYPE_CHECKING, Callable
label_desc: Use image node_id 6 for calling the ExprNameNameSpace obj's underlying member method code with example usage: obj.to_lowercase() and returns: self